Abstract: Abstract: The development of an effective method to improve the quality of ripened pu-erh tea is of significant scientific and commercial importance. In this study, Debaryomyces hansenii PETY002 isolated from pu-erh tea was used for enhanced fermentation (EF) in pu-erh tea. The total number of yeast colonies in the EF group was significantly higher than that in the normal fermentation (NF). The sensory evaluation revealed that the tea infusion of the EF group was darker in color, mellower in taste, and had a mushroom aroma. The results of measurement of characteristic components showed that the content of theabrownins and water extracts increased significantly (p < 0.05), while the content of tea polyphenols, catechins (C, EGC, GC, EGCG), and caffeine decreased significantly (p < 0.05). Compared with NF, there was little difference between flavonoids and amino acids components in EF. Microbial community analysis revealed that Debaryomyces were dominant fungus in the EF. Furthermore, Debaryomyces and Thermomyces exhibited a competitive relationship. Correlation analysis revealed that Debaryomyces were significantly positively correlated with theabrownins, while negatively correlated with soluble sugars and theaflavins (|r| ≥ 0.7, p < 0.05). In conclusion, the inoculation of D. Hansenii PETY002 for enhanced fermentation changed the diversity and composition of the microbial community in fermentation of pu-erh tea, which improved the quality of pu-erh tea through interactions with other dominant microorganisms.

Key words: Keywords: Debaryomyces hansenii, pu-erh tea, enhanced fermentation, characteristic components, microbial communities